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Optimization, fabrication and characterization of a binary subwavelength cylindrical terahertz lens
S.I. Kharitonov 1,2, V.S. Pavelyev 1,2, N.L. Kazanskiy 1,2, Y.S. Strelkov 1,2, K.N. Tukmakov 1, A.S. Reshetnikov 1, S.V. Ganchevskaya 1,2, V.V. Gerasimov 3,4, B.A. Knyazev 3,4

1 IPSI RAS – Branch of the FSRC "Crystallography and Photonics" RAS,
443001, Samara, Russia, Molodogvardeyskaya 151;
2 Samara National Research University, 443086, Samara, Russia, Moskovskoye Shosse 34;
3 Novosibirsk State University, 630090, Russia, Novosibirsk, Pirogovа St. 1;
4 Budker Institute of Nuclear Physics, 630090, Novosibirsk, Russia, Lavrentiev Ave 11

 PDF, 981 kB

DOI: 10.18287/2412-6179-CO-1194

Pages: 62-67.

Full text of article: Russian language.

Abstract:
A problem of optimizing the subwavelength microrelief of a binary cylindrical transmissive diffractive lens (DL) with a 300-mm focal length for a wavelength of λ=141 μm was considered. High-resistivity silicon was chosen as the DL substrate material. The angle of incidence of the illuminating beam was taken to be π/6. The optimization parameters were the height of the DL profile and the fill factor of the groove. The main goal of optimizing the design was to increase the diffraction efficiency of the lens. The DL diffraction efficiency was calculated using a Fourier mod method. The DL was fabricated by plasma-chemical etching (Bosch process) of the surface of a silicon substrate. The diffraction efficiency of the calculated lens was estimated to be 70%. However, a full-scale experiment showed the real efficiency to be much lower. These differences are related to both errors in the manufacturing process of the DL and non-ideal thickness parameters of the silicon wafers.

Keywords:
binary lens, subwavelength microrelief, terahertz radiation, diffractive optical elements.

Citation:
Kharitonov SI, Pavelyev VS, Kazanskiy NL, Strelkov YS, Tukmakov KN, Reshetnikov AS, Ganchevskaya SV, Gerasimov VV, Knyazev BA. Optimization, fabrication and characterization of a binary subwavelength cylindrical lens for the terahertz range. Computer Optics 2023; 47(1): 62-67. DOI: 10.18287/2412-6179-CO-1194.

Acknowledgements:
The work was supported by the Russian Science Foundation (project No. 19-72-20202) and conducted using a unique installation "Novosibirsk free electron laser" using equipment "Siberian Center for Synchrotron and Terahertz Radiation".

References:
  1. Kulipanov GN, Bagryanskaya EG, Chesnokov EN, Choporova YuYu, Gerasimov VV, Getmanov YaV, Kiselev SL, Knyazev BA, Kubarev VV, Peltek SE, Popik VM, Salikova TV, Scheglov MA, Seredniakov SS, Shevchenko OA, Skrinsky AN, Veber SL, Vinokurov NA. Novosibirsk free electron laser-facility description and recent experiments. IEEE Trans Terahertz Sci Technol 2015; 5(5): 798-809. DOI: 10.1109/TTHZ.2015.2453121.
  2. Walsby ED, Wang S, Xu J, Yuan T, Blaikie R, Durbin SM, Zhang X-C, Cumming DRS. Multilevel silicon diffractive optics for terahertz waves. J Vac Sci Technol B 2002; 20(6): 2780-2783. DOI: 10.1116/1.1518021.
  3. Agafonov AN, Volodkin BO, Kaveev AK, Knyazev BA, Kropotov GI, Pavel'ev VS, Soifer VA, Tukmakov KN, Tsygankova EV, Choporova YuYu. Silicon diffractive optical elements for high-power monochromatic terahertz radiation. Optoelectronics, Instrumentation and Data Processing 2013; 49(2): 189-195. DOI: 10.3103/S875669901302012X.
  4. Komlenok MS, Kononenko TV, Konov VI, Choporova YuYu, Osintseva ND, Knyazev BA, Pavelyev VS, Tukmakov KN, Soifer VA. Silicon diffractive optical element with piecewise continuous profile to focus high-power terahertz radiation into a square area. J Opt Soc Am B 2021; 38(8): B9-B13. DOI: 10.1364/JOSAB.425286.
  5. Kononenko TV, Knyazev BA, Sovyk DN, Pavelyev VS, Komlenok MS, Komandin GA, Konov VI. Silicon kinoform cylindrical lens with low surface roughness for high-power terahertz radiation. Opt Laser Technol 2020; 123: 105953. DOI: 10.1016/j.optlastec.2019.105953.
  6. Agafonov AN, Knyazev BA, Pavelyev VS, Akhmetova EI, Platonov VI. Elements of the terahertz power reflective optics with free-form surfaces. Optoelectronics, Instrumentation and Data Processing 2019; 55(2): 148-153. DOI: 10.3103/S8756699019020067.
  7. Agafonov AN, Volodkin BO, Kachalov DG, Knyazev BA, Kropotov GI, Tukmakov KN, Pavelyev VS, Tsypishka DI, Choporova YuYu, Kaveev AK. Focusing of Novosibirsk Free Electron Laser (NovoFEL) radiation into paraxial segment. J Mod Opt 2016; 63(11): 1051-1054. DOI: 10.1080/09500340.2015.1118163.
  8. Pavelyev VS, Choporova YuYu, Osintseva ND, Tukmakov KN, Knyazev BA. Control of transverse mode content and polarization structure of terahertz coherent beams. Computer Optics 2019; 43(6): 1103-1108. DOI: 10.18287/2412-6179-2019-43-6-1103-1108.
  9. Pavelyev VS, Degtyarev SA, Tukmakov KN, Reshetnikov AS, Knyazev BA, Choporova YuYu. Silicon subwavelength axicons for terahertz beam polarization transformation. J Phys Conf Ser 2021; 1745: 012022. DOI: 10.1088/1742-6596/1745/1/012022.
  10. Rogalin V, Kaplunov I, Kropotov G. Optical materials for the THz range. Opt Spectrosc 2018; 125: 1053-1064. DOI: 10.1134/S0030400X18120172.
  11. Komlenok MS, Volodkin BO, Knyazev BA, Kononenko VV, Kononenko TV, Konov VI, Pavelyev VS, Soifer VA, Tukmakov KN, Choporova YuYu. Fabrication of a multilevel THz Fresnel lens by femtosecond laser ablation. Quantum Electron 2015; 45(10): 933-936. DOI: 10.1070/QE2015v045n10ABEH015890.
  12. Volkov AV, Kazanskiy NL, Soifer VA, Usplenyev GV. Technology of DOE fabrication. In Book: Soifer VA, ed. Methods of computer optics [In Russian]. Moscow: "Fizmatlit" Publisher; 2000: 239-310.
  13. Soifer VA, ed. Diffraction nanophotonics [In Russian]. Moscow: "Fizmatlit" Publisher; 2011. ISBN: 978-5-9221-1237-6.
  14. Doskolovich LL Calculation of diffraction gratings within the framework of a rigorous electromagnetic theory [In Russian]. Samara: Samara State University Publishing House; 2007. ISBN: 978-5-7883-0607-0.
  15. Doskolovich LL, Kharitonov SI, Kazansky NL, Tulupova EA, Skuratov SA. Asymptotic solutions of the Helmholtz equation for pseudoperiodic structures. Computer Optics 2005; 27: 50-55.
  16. Doskolovich LL, Tyavin EV. Designing binary diffraction gratings with etching wedge. Computer Optics 2005; 27: 17-20.
  17. Savelyev DA. The comparison of laser radiation focusing by diffractive axicons and annular gratings with variable height using high-performance computer systems. 2021 Photonics & Electromagnetics Research Symposium (PIERS) 2021: 2709-2716. DOI: 10.1109/PIERS53385.2021.9694860.

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